1. Field of the Invention
The present invention relates to a refrigeration cycle and a method for determining a capacity of a receiver of a refrigeration cycle.
2. Background of the Related Art
One of the conventional refrigeration cycles is disclosed in Japanese Patent Laid-open No. 9-33139 published on Feb. 7, 1997.
The prior art refrigeration cycle comprises a refrigerant compressor that is adapted to compress refrigerant, a refrigerant condenser that is provided with a plurality of condensing tube portion for condensing the refrigerant flowing from the refrigerant compressor and with a refrigerant combining portion for combining the refrigerants flowing from the plurality of condensing tube portion, a receiver that separates the refrigerant from the refrigerant combining portion of the refrigerant condenser into gaseous and liquid refrigerant to make only liquid refrigerant flow, a supercooling device that is provided with a refrigerant distribution portion for distributing the refrigerant flowing from the receiver and with a supercooling tube portion for supercooling the refrigerant distributed from the refrigerant distribution portion, a sight glass that is adapted to watch the state of the refrigerant flowing from the supercooling device, an expansion valve that is adapted to make the refrigerant flowing from the sight glass expanded, and a refrigerant evaporator that is adapted to make the refrigerant flowing from the expansion valve evaporated. If a required capacity of the fluid receiver is represented by VR, a sum of a capacity of the refrigerant condenser and a capacity of the supercooling device is represented by VCOND, a capacity of the refrigerant evaporator is represented by VEVA, a capacity of the supercooling tube portion is represented by VSC, and a sum of capacity of the refrigerant combining portion and a capacity of the refrigerant distribution portion is represented by Vh, relational expressions as described below;
V1=1.52xc3x9710xe2x88x923xc2x7VCOND(CC)+34.3xc3x9710xe2x88x923xc2x7VEVA(CC) 
V2=170(CC) 
V3=0.65xc3x97(Vh+VSC)(CC) 
VRxe2x89xa70.8xc3x97(V1+V2xe2x88x92V3)(CC) 
VRxe2x89xa70.8xc3x97(V1+V2xe2x88x92V3)(CC) are satisfied. 
The above-mentioned refrigeration cycle is capable of providing a relatively small-sized receiver and preventing an effective heat exchanging area of a core of the refrigerant condenser from being reduced.
However, the components of the refrigeration cycle have different specifications according to the kind of vehicle and the variations of the cooling load is substantially irregular, such that it is difficult to measure a total capacity in the refrigeration cycle. Therefore, it is not easy that the above-described relational expressions shown in the conventional refrigeration cycle are actually applied.
Upon the process of brazing, besides, the refrigerant condenser integrated with the receiver is not heated evenly in a brazing furnace due to the variations of the heat capacity caused by the change of the capacity of the receiver, which causes a brazing failure that will result in an increase of the number of bad products.
To avoid the brazing failure, the receiver is designed to have a relatively small capacity, but this is not considered that the local temperature difference in the brazing furnace still exists. Moreover, a correlative relationship between the refrigerant condenser and the receiver is not considered at all, and as the amount of stocked refrigerant of the receiver is decreased, refrigerant supply is not carried out stably in accordance with the variations of the cooling load. This of course causes the efficiency of the refrigeration cycle to be greatly low.
Accordingly, the present invention is directed to a refrigeration cycle and a method for determining a capacity of a receiver of a refrigeration cycle that substantially obviates one or more problems due to limitations and disadvantages of the related art.
An object of the present invention is to provide a refrigeration cycle that is provided with a compressor, a condenser, a receiver, an expansion valve and an evaporator, wherein a correlative relationship between a capacity of the condenser and a capacity of the receiver is obtained, and with the relational expression, the capacity of the receiver can be easily obtained.
Another object of the present invention is to provide a method for determining a capacity of a receiver in a refrigeration cycle that has a compressor, a condenser, the receiver, an expansion valve and an evaporator, wherein the capacity of the receiver can be easily obtained by using a capacity of the condenser.
Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objectives and other advantages of the invention may be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
According to an aspect of the present invention, there is provided a refrigeration cycle that has a compressor, a condenser, a receiver, an expansion valve and an evaporator, wherein if a capacity of the condenser is represented by CVT and a capacity of the receiver is represented by RV, a relational expression of 29.71xc3x97ln(CVT)+35xe2x89xa6RVxe2x89xa641.103xc3x97ln(CVT)+74.3 is satisfied.
According to another aspect of the present invention, there is provided a method for determining a capacity of a receiver in a refrigeration cycle that has a compressor, a condenser, a receiver, an expansion valve and an evaporator, wherein if a capacity of the condenser is represented by CVT and a capacity of the receiver is represented by RV, a relational expression of 29.71xc3x97ln(CVT)+35xe2x89xa6RVxe2x89xa641.103xc3x97ln(CVT)+74.3 is satisfied.
It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.